You are probably right. The R2-5 relay was only one of several relays affected by the a/g sensor. The R2-5 relay failing by itself could have caused their problem. The final report wasn't very conclusive on what caused the R2-5 relay to be in air mode. Corrosion in the socket could have done it, or a faulty relay which should have been easy to check. Being put in a situation as they were kept me interested in the outcome but guess this is all we will know.